None:- No action will take place on related records in the RentalTable when you delete a record in the CarTable.
Cascade:- All records in RentalTable related to the record being deleted in CarTable will also be deleted.
Restricted:- The user will get a warning saying that the record in the CarTable cannot be deleted because transactions exist in table RentalTable. The user will be unable to delete the record in CarTable if one or more related records exist in the RentalTable.
Cascade + Restricted:- This option is used when deleting records through more than two levels. Let's say that another table existed that had a cascade delete action against CarTable and the CarTable had a
Cascade + Restriced delete action against Rental Table. If the record in the top level table was about to be deleted it would also delete the related records in CarTable. In turn, all the records in RentalTable related to the records being deleted from CarTable would also be deleted. If only a record in CarTable was about to
be deleted, the user would get the same message as when using the Restricted method.
Cascade:- All records in RentalTable related to the record being deleted in CarTable will also be deleted.
Restricted:- The user will get a warning saying that the record in the CarTable cannot be deleted because transactions exist in table RentalTable. The user will be unable to delete the record in CarTable if one or more related records exist in the RentalTable.
Cascade + Restricted:- This option is used when deleting records through more than two levels. Let's say that another table existed that had a cascade delete action against CarTable and the CarTable had a
Cascade + Restriced delete action against Rental Table. If the record in the top level table was about to be deleted it would also delete the related records in CarTable. In turn, all the records in RentalTable related to the records being deleted from CarTable would also be deleted. If only a record in CarTable was about to
be deleted, the user would get the same message as when using the Restricted method.
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